Air Conditioning System Treatment Applicator

ABSTRACT

An applicator for introducing an air conditioning system treatment into an air conditioning system refrigerant flow path. The applicator comprises a reservoir carrying the treatment, the reservoir having first and second caps closing first and second reservoir openings, each of the first and second caps including a hose fitting. First and second hoses are connected between respective first and second valves in the refrigerant flow path and the respective first and the second fittings. A pressure differential between the first and the second valves (a higher pressure at the first valve than at the second valve) forces the treatment from the reservoir through the second hose into the second valve in the refrigerant flow path.

The present application claims the benefit under Section 119(e) of the provisional application filed on Dec. 21, 2008 and assigned application No. 60/871,267.

FIELD OF THE INVENTION

The present invention relates generally to air conditioning systems and specifically to an applicator for injecting an air conditioning system treatment into the system's coolant path.

BACKGROUND OF THE INVENTION

An air conditioning system provides a cooing effect according to a closed thermal refrigeration cycle. As illustrated in FIG. 1, an air conditioning system 10 comprises three primary components, a compressor 14, a condenser 18 and an evaporator 22 interconnected by pipes 26 carrying a refrigerant. The refrigerant alternates between a liquid state and a gas state as it circulates through a high-pressure section and a low-pressure section of the system 10.

A pressurized liquid refrigerant, such as Freon, enters the evaporator 22 via an expansion valve 32 that lowers the liquid pressure, allowing the refrigerant to vaporize (boil) at a lower temperature, thus ensuring that the refrigerant absorbs a maximum quantity of heat as it passes through the evaporator coif. As the reduced-pressure, liquid absorbs heat from the air (the cold refrigerated space) surrounding the evaporator 22 the refrigerant temperature reaches its boiling point and evaporates to a gas.

From the evaporator 22, the low-pressure gas flows to the compressor 14 where the gas is compressed to a high-pressure state. The higher pressure permits the gas to give up more heat (than a lower pressure gas), ensuring that the gas condenses to a liquid state during the next stage (condenser) of the refrigerate cycle. From the compressor 14, the pressurised gas enters the condenser 18 where the gas condenses to a high-pressure liquid, giving up heat to the warm environment surrounding the condenser 18. The refrigerant then returns to the evaporator 22 via the expansion valve 32 as a low pressure liquid.

An electric motor or an internal combustion engine (not shown) supplies fee mechanical rotational energy required to operate the compressor 14 to compress the vapor and circulate the refrigerant Power consumed by the air conditioning system 10 is directly related to the energy required to operate the compressor 14 and in turn related to compressor Motional forces that must be overcome by the electric motor or the internal combustion engine. Higher frictional forces raise the power consumption of the compressor 14. Generally, a lubricating oil is added to the system to circulate with the refrigerant to reduce these frictional forces.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more easily understood and the advantages and uses thereof more readily apparent when the following detailed description of the present invention is read in conjunction with the figures wherein:

FIG. 1 illustrates a prior art air conditioning system.

FIG. 2 illustrates an applicator of the present invention for loading an air conditioning system treatment into the air conditioning system of FIG. 1.

FIG. 3 illustrates elements associated with a process for loading the treatment into an air conditioning system.

FIG. 4 illustrates elements associated with a process for loading the treatment into the applicator of the present invention.

FIGS. 5 and 6 illustrate another embodiment of an end cap for use with the applicator of FIG. 2.

In accordance with common practice, the various described device features are not drawn to scale, but are drawn to emphasize specific features relevant to the invention. Like reference characters denote like elements throughout the figures and text.

DETAILED DESCRIPTION OF THE INVENTION

Before describing in detail the exemplary methods and apparatuses related to an air conditioning system treatment applicator, it should be observed that the present invention resides primarily in a novel and non-obvious combination of elements and process steps. So as not to obscure the disclosure with details that will be readily apparent to those skilled in the art, certain conventional elements and steps have been presented with lesser detail, while the drawings and the specification describe in greater detail other elements and steps pertinent to understanding the invention.

The following embodiments are not intended to define limits as to the structure or method of the invention, but only to provide exemplary constructions. The embodiments are permissive rather than mandatory and illustrative rather than exhaustive.

An air conditioning system treatment is described in a co-pending and co-owned patent application entitled Air Conditioning System Treatment filed on Nov. 16, 2006 and assigned application Ser. No. 11/560,506. which is hereby incorporated by reference.

The system treatment described in the patent application is loaded into an air conditioning system, such as the prior art air conditioning system 10 of FIG. 1, using an applicator 100 as illustrated in FIG. 2. The applicator 100 comprises a hollow elongated reservoir 104, such as a tubular member, carrying the air conditioning system treatment. In one embodiment the reservoir holds about 6.5 ounces of treatment. The process of loading the treatment into the reservoir 100 is described below. Each end of the reservoir 104 is dosed by an end cap 108 and 110. Each end cap 108/110 further comprises a fitting 112 for connecting the applicator 100 to an existing air conditioning system for adding the treatment within the reservoir 104 to the system's refrigerant path. A fitting cap 114 is removably affixed to each fitting 112.

FIG. 3 illustrates the elements associated with dispensing the air conditioning treatment from the applicator 100 to an air conditioning system, such as the air conditioning system 10 of FIG. 1. Each fitting 112 (not visible in FIG. 3) removably receives a first end of a hose 126A or 126B. A second end of a hose 126A is connected to a normally-closed Schrader valve 122A (referred to as an air conditioning system service port) at the high pressure outlet of the compressor 14. Typically the high-side pressure is about 155 psi. A second end of the hose 126B is connected to a normally-closed Schrader valve 1228 at the low pressure inlet (or low side having a pressure of about 65 psi) of the compressor 14. Thus as can be seen, the reservoir 104 is connected across the compressor inlet and outlet ports. Each hose 126A and 126B further comprises a shut-off valve 130 for controlling the low of fluid therethrough. Only one valve 130 is required according to the present invention.

The operation of connecting each hose 126A/126B to its respective valve 122A/122B actuates a condition-controlling pin that opens the valve 122A/122B. The technician then purges the hoses 126 of air according to techniques known in the art. The technician opens the shut-off valves 130, permitting the air conditioning refrigerant to flow from the valve 122A (the high pressure side) through the reservoir 104 and back into the air conditioning system 120 at the valve 122B (the low pressure side), in a direction illustrated by arrowheads 140. As the refrigerant flows through the reservoir 104 the high-side pressure overcomes the pressure within the reservoir 104 and forces the air conditioning treatment fluid from the reservoir 104 into the air conditioning system. Generally, the process of loading the treatment into the air conditioning system takes less than about 20 seconds. The reservoir 104 may comprise a clear material permitting the technician to determine when all the treatment has been removed from the reservoir 100. The technician then closes the valves 130 to isolate the applicator 100 from the air conditioning system. The hoses 126 are removed, causing the valves 122A and 122B to return to their normally closed state.

In one embodiment an agitating element 116 (see FIG. 2) is disposed within the reservoir 104 for agitating the treatment to promote mixing of the treatment and the refrigerant during the removal process.

According to another (optional) embodiment for injecting the treatment into the refrigerant system, the treatment is mixed with a pressurized canister of refrigerant. When connected to the valve 1228, the pressure within the canister forces the refrigerant and the treatment from the canister into the air conditioning system. Such a canister 200 is illustrated in phantom in FIG. 3 connected to the valve 1228 via a hose 202. Disadvantageously, this injection method introduces some refrigerant into the air conditioning system, along with the treatment, and therefore may not be desired.

Because air in the refrigerant path 124 is not desired, to avoid injecting air into the refrigerant path, it is preferred to purge all air from the reservoir 104 during or after filling the reservoir 104 with the air conditioning treatment. To accomplish this purging according to one embodiment, the applicator 100 is oriented in a vertical position during the treatment filling process. The upper and lower fitting caps 114 are removed from the respective upper and lower fittings 112 and treatment is pumped into the reservoir 104 from the bottom through a lower hose 150 (see FIG. 4) connected to the lower fitting 112. The fluid flows vertically upwardly through the reservoir 104 eventually reaching the upper fitting 112. An upper hose 152 connected to the upper fitting 112 carries air from the reservoir 104 as the air conditioning treatment fluid enters. Preferably the upper hose 152 comprises a transparent material permitting visual detection of the air or the treatment within the upper hose 152. The loading process is terminated when the treatment is detected within the upper hose 152.

The upper hose 152 is then removed and the upper fitting cap 114 (see FIG. 2) is removably affixed to the upper fitting 112. The lower hose 150 is removed from the lower fitting 112 and the lower fitting cap 114 is removably affixed to the lower fitting 112. Note that it is not necessary to invert the applicator 100 prior to removing the lower hose 150 as the pressure differential between the upper and lower ends of the reservoir 104 retains the treatment within the reservoir 104. The applicator 100 is now ready for use as described above; the reservoir 104 is filled with the air conditioning treatment and air has been evacuated from the reservoir 104.

In one embodiment each fitting 112 is formed integral with its respective end cap 108/110. In another embodiment each cap 108/110 comprises a polyvinyl chloride cap into which the fitting 112 is adhesively inserted. The end caps 112 are further adhesively affixed to the reservoir 104 according to known techniques, including use of an adhesive.

In another embodiment, an end cap 170 (particularly for use as the upper end cap 108 when oriented as illustrated in FIG. 4) comprises fins or fingers 180 extending inwardly into the reservoir 104 (from an inside surface of an upper region 170A). The end cap 170 further comprises wall surfaces 107B (extending along an exterior surface of the reservoir 104). See FIG. 5 illustrating a view into an interior of the end cap 170 and FIG. 6 illustrating a side view of the end cap 170. In the latter view it is assumed that the end cap 170 comprises a transparent material and thus the fingers 180 are visible.

After completing the process of filling the reservoir 104 with the treatment, as described above, the end cap 170 may be affixed to the reservoir 104 in lieu of the end cap 108. The fingers 180 extending into the interior region of the reservoir 104 ensure that substantially all the air is evacuated therefrom by forcing and remaining air through the upper fitting 112.

While the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalent elements may be substituted for the elements thereof without departing from the scope of the invention. The scope of the present invention further includes any combination of elements from the various embodiments set forth herein. In addition, modifications may be made to adapt a particular situation to the teachings of the present invention without departing from its essential scope. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include alt embodiments falling within the scope of the appended claims. 

1. An applicator for introducing an air conditioning system treatment into an air conditioning system refrigerant flow path through first and second hoses connected between the refrigerant flow path and the applicator, the flow path further comprising first and second serial valves, the applicator comprising: a reservoir carrying the treatment; first and second caps closing the reservoir; a first and a second fitting within the respective first and second caps; wherein the first and the second hoses are connected between the respective first and second valves and the first and the second fittings, and wherein a pressure differential between the first and the second valves forces the treatment from the reservoir through the second hose into the refrigerant flow path.
 2. The applicator of claim 1 wherein the first end cap comprises fingers extending from an interior surface of the first end cap into an interior region of the reservoir.
 3. The applicator of claim 1 further comprising an agitator within the reservoir for agitating the treatment to promote mixing of the treatment and the refrigerant.
 4. The applicator of claim 1 wherein the reservoir comprises a hollow tubular element, and wherein the first and the second caps are disposed at opposing ends of the tubular element.
 5. The applicator of claim 1 wherein the first and the second valves each comprise a normally-dosed pin that is moved to an open condition when the first and the second hoses are connected to the respective first and second valves.
 6. The applicator of claim 1 wherein the first and the second valves each comprise a Schrader valve.
 7. The applicator of claim 1 wherein the first and the second valves are disposed at the respective high and low pressure sides of a compressor in the refrigerant flow path.
 8. The applicator of claim 7 wherein flow of refrigerant from the high pressure side to the low pressure side through the reservoir forces the treatment from the reservoir through the second hose into the refrigerant flow path.
 9. The applicator of claim 7 wherein a pressure differential between the first and the second valves, with the pressure greater at the first valve than at the second valve, forces the treatment from the reservoir through the second hose into the refrigerant flow path.
 10. A method of introducing an air conditioning system treatment in a reservoir into an air conditioning system refrigerant Bow path, the method comprising: connecting a first opening in the reservoir to a first end of a first hose; connecting a second end of the first hose to a first valve in the refrigerant flow path; connecting a second opening in the reservoir to a first end of a second hose; connecting a second end of the second hose to a second valve in the refrigerant low path, wherein a pressure at the first valve is greater than a pressure at the second valve; and opening the first and the second valves to create a higher pressure at the first opening than a pressure at the second opening, wherein a pressure difference forces the treatment from the second opening into the refrigerant flow path.
 11. The method of claim 10 wherein the step of connecting the second end of the first hose to the first valve opens the first valve and the step of connecting the second end of the second hose to the second valve opens the second valve.
 12. The method of claim 10 wherein one or both of the first and the second hoses further comprises a respective third and fourth valve, the method further comprising opening the third and the fourth valves.
 13. A method for loading an air conditioning system treatment into an applicator comprising a tubular reservoir, the method comprising: positioning the reservoir in a vertical orientation having an upper end above a lower end, the upper end open to the atmosphere and the lower end terminated in a lower end cap having a lower fitting therein; attaching a supply hose to the tower fitting; injecting treatment into the reservoir through the supply hose, during the injecting process air escapes through the upper end; detecting treatment leaving the upper end; closing the upper end by attaching an upper end cap thereto; removing the supply hose from the lower fitting; and attaching a tower fitting cap to the lower fitting.
 14. The method of claim 13 wherein the upper end cap comprises an upper fitting open to the atmosphere and a transparent drain hose connected to the upper fitting, and wherein the step of detecting treatment leaving the upper end further comprises visually detecting treatment within the transparent drain hose.
 15. The method of claim 13 wherein the upper end cap comprises upper fitting open to the atmosphere, and wherein the step of closing the upper end further comprises attaching a fitting cap to the upper fitting. 